Earthquake Early Warning System for Railways and Its Performance

Scaling relation between earthquake magnitude and the departure time from P wave similar growth

“…Rapid determination of earthquake magnitude ( M ) is essential for earthquake early warning (EEW) that can provide a countermeasure against earthquake loss [e.g., Hoshiba et al , ; Espinosa‐Aranda et al , ; Yamamoto and Tomori , ; Given et al , ]. A number of methodologies have been proposed to determine M rapidly for EEW.…”

<b>Improved Algorithms of Seismic Parameters Estimation and Noise Discrimination in Earthquake Early Warning</b>

“…When the safty of railway facilities and running vehicles are threatened by strong ground motion during earthquakes, railway operators stop trains as soon as possible [1,2,3]. Since P-wave propagation velocity is faster than S-wave, P-wave information is an effective source to stop trains rapidly.…”

<b>Earthquake Early Warning Using Ocean Bottom Seismic Data for Railways</b>

“…The conventional EEW system for railways employs Pand S-wave warning methods [1]. The P-wave warning estimates epicenter location [e.g., 5,6] and magnitude [e.g., 7,8] from the initial P-wave waveform and determines the area of potential damage using the M-Δ diagram [1,4].…”

“…The EEW systems issue alerts to halt trains or to reduce the speeds of trains by measuring and analyzing seismic ground motions, when it is deemed that the earthquake event may cause damage to railway structures. Conventionally, railway company EEW systems used data collected from their own seismic stations installed along tracks (track-side seismometer) or away from tracks to be able detect earthquakes earlier (front-detection seismometer) [1]. Even though they also make use of public EEW data published by the Japan Meteorological Agency (JMA) to improve system redundancy, this data is derived only from land-based seismographs.…”